Vehicles commonly employ transmissions to transfer power between an internal combustion engine and vehicle wheels. Hybrid and micro-hybrid vehicles may include control systems that are configured to shut down the engine of the vehicle in order to increase fuel economy and reduce emissions. In certain architectures, the vehicle also may have a traction motor connected at the input of the transmission, in which the traction motor is electrically connected to a traction battery. The motor may be used in either a motoring mode in which energy from the battery is used to supplement the engine power or in a generating mode in which the motor converts mechanical energy into electrical energy which is stored in the battery. Some vehicles also include a starter/generator, such as a belt integrated starter/generator (BISG) that is electrically connected to an auxiliary battery, typically a low-voltage battery. A vehicle with a BISG may supply a charge to the low-voltage battery by either the BISG or the traction motor/traction battery.